Charge-Energy Coupling Drives Ag₆ Nanocluster-Amine Self-Assembly

The charge-energy coupling mechanism in solution self-assembly remains poorly understood, limiting the predictable nanostructure design and precise morphology control. Here, the silver nanocluster (Ag₆NCs)-octadecylamine (ODA) system was used as a model, and a multiscale simulation framework was established to analyze continuous morphology transitions under coupled pH and concentration regulation. A two-dimensional (C-pH) phase diagram was constructed, revealing a continuous evolution from clusters to fiber-like intermediates, porous lamellae, and large square lamellae. Thermodynamic analysis showed that concentration drives structural rearrangement through accumulation of nonbond interaction energy, whereas pH controls the rearrangement pathway through functional-group ionization and the interfacial charge environment. Experiments across the full parameter space, combined with morphology characterization, DLS, PDI, and zeta potential analyses, validated the simulations and supported a mechanism of local charge compensation-promoted rearrangement and interfacial reconstruction-enabled stabilization. A cross-scale link from molecular ionization to mesoscale morphology was established, and a charge-energy coupling framework was established to provide a mechanistic understanding of morphological evolution in complex self-assembly systems.